Method of reclaiming used lubricating oils



March l5, 1932.

W. S. BAYLIS METHOD OF RECLAIMING USED LUBRICATING OILS Filed Oct. 14. 1926 Q53@ HGH@ All llnlll Nm. m,

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Patented Mar. l5, 1932 N Urrea WALTER.' S. BAYLIS, 0F LOS ANGELES, CALIFORNIA, ASSIGNOR, BY MESN'E .ASSIGN- MENTS, TO FILTROL COMANY 0F CALIFORNIA, A CORPORATIUN 0F CALIFORNIA METHOD vOF RECLAEMENG 'USED LUBBIGATTNG UTLS Application led october 14,. w26. Serial No. 141,588..

My invention relates to oil refining processes, and it consists of a process of reclaiming used lubricating oil.

lt is well known that lubricating oil loses its lubricating qualities by reason of its being impregnated With colloidal carbon, organic and inorganic acids, foreign matter and other impurities such as gasoline.

It is an object of my invention to provide a reclaiming process for treating used lubricating oil whereby the undesirable substances may be removed and the oil thus made suitable for reuse.

It is another object-of this invention to provide a reclaiming process for treating used lubricating oil in which the used lubricating oil is mixed with an adsorptive material which adsorbs all the impurities of the oil with the exception of the very light distillates, the adsorptivematerial carrying the impurities afterwards being separated from the lubricating oil byfiltration.

It is another object of my invention Vtoy provide a' process of this character in which the lubricating oil is subjected to the action of hot vapors in order to evaporate the light distillates therefrom and to reducethe oil to a. desired viscosity.

I have found that by addingsilicate of soda to the used lubricating oil and adsorptive material, the fattyV or 'organic acids are readily collected and adsorbed by the adsorptive material.

It is, therefore, an object of my invention to provide a process for recovering used lubricating oil in which silicate of soda or some other agglomerating agent is mixed with the oil and adsorptive material.

It is also an object of my invention to provide a process of this character in which the oil is distilled under a high vacuum to prevent oxidization and cracking of the oil.

' Other objects and advantages of the invention will be made evidenthereinafter.

Referring to the drawings in which an apparatus for conducting my invention is shown, v

1 is a mixer, 2 is a pressure pump, 3 is a primary lter press, 4 is a still, 5 is a liquid trap,'6 is a condenserr? is a vacuum pump,

8 is an expansion vessel, 9 is a' pressure pump, 10 is a secondary filter and 11 is an oil cooler.

The mixer 1 consists of a shell 12 having a conical bottom 3 and which is open at the top end thereof. Surrounding the shell 12 M is a jacket 14 providing a heating chamber 15 which has pipes 16 connected thereto by means of which a suitable heating medium such as steam is supplied to and taken from the chamber 15, this heating medium being for the pur ose of heating the interior of the mixer 1. ixing paddles 18 are positioned in the mixer l, being rigidly secured on a shaft 19 which is supported by bearings 17. The shaft 19 is adapted to be driven by gears 20 which are secured at the upper end of the shaft 19. Used lubricating oil is supplied to the mixer 1 by means of an oil pipe 13. This used lubricating oil contains colloidal carbon, foreign matter, acids and other impurities such as distillates which have been added thereto during its use.

A small percentage of adsorptive material is added to the oil in the mixer 1 and is thoroughly mixed therewith by means of the mixing paddles 18 which are operated when the shaft 19 rotates. Also, a small percentage of a glomerating agent is added to the mixture of oil and adsorpt-ive vmaterial by means of a pipe 21 and is also mixed with the oil. The

temperature of the mixture in the mixer 1 is raised to about 220 F. The adsorptive material during the time that it is being mixed with the oil adsorbs the foreign material, colloidal carbon and other impurities with which the lubricating oil is impregnated. The agglomerating agent operates to collect all of the fatty or organic acids so that they may be readilyadsorbed by the adsorptive material. All of the organic and inorganic acids are thus removed from the lubricating oil dand the lubricating oil is entirely neutralize When the mixing has continued a sufcient length of time to ypermit all of the undesirable substances to be adsorbed by the adsorptive material, the mixture is removed to the primary filter press 3. A pipe 24 extends from the conical bottom 3 of the mixer 1 to the pressure pump 2,this pipe 24 having a valve 22 which is closed while the mixing is being carried on in the mixer. Extending from the pressure pump 2 to the primary ilter press 3 is a pipe 23. The valve 22 is opened (when the mixing is complete) and the pressure pump 2 is set into operation to pump the mixture from the mixer 1 into the lter press 3.

The filter press 3 is of standard construcf sirable substances of the lubricating oil is too coarse to pass through the bags 33 and therefore collects in cakes 37 on the exteriors of the bags, as shown in the drawing. This operation removes all the impurities or moisture and leaves a clear oil containing only the very light distillates. A

The filtered oil and light distillates are carried to the still 4 by means of a pipe 38 having a valve 39 which connects with the manifold 35 and the still 4. The still 4 consists of a shell 41 having a conical bottom 42 and a tight top 43. The pipe 38 connects with the interior of the still 4 through the top 43. Mixing paddles 44 are supported in the shell 41 by a shaft 45 which is rotatable in bearings 46. The shaft 45 extends from the top 43 of the still 4 and is adapted to be operated by gearing 47. The shell 41 is provided with a jacket 48 to which pipes 49 connect for supplying a heating medium to a chamber 51 provided-between the jacket and shell-for the purpose of heating the interior of the still 4.

The clear oil containing the light distillates is-mixed-with a small percentage of fresh adsorptive material in the still 4 by the oper-` ation of the mixing paddles 44, this adsorptive material being introduced into the still 4 through an opening closed by a tight cover 52. A high vacuum is placed upon the interior of the still 4 by means of a pipe 53 which connects to the interior of the still 4 through the tight top 43 thereof.

During the mixing of the clear oil and the fresh adsorptive material in the still 4, steam is introduced into the still by means of a pipe 54 having a valve 55, said pipe 54 extending through the conical bottom 42 of the still. This steam passes upwardly through the mixture of clear oil and adsorptive material and heats the oil to the extent thatthe light distillates are distilled therefrom.

The vapor 'composed of steam and light distillate vapors is drawn through the pipe 53 by .the vacuum created by the vacuum pump 7. The pipe 53 connects to the liquid trap 5. This liquid trap 5 consists of a she-ll 57 having a baflie plate 58. The Vapor is introduced into the liquid trap 5 and passes around the baiiie plate 58. The vapor is de* prived of any particles of liquid which it may carry during its passage through the liquid trap 5. A pipe 61 connects the interior of the liquid trap 5 with the condenser 6.

The condenser 6 consists of a shell 62, the ends of which are closed by tight covers 63. Intermediate heads 64 are secured inside the shell 62 between which pipes 65 are extended. Pipes 67 are connected to the space between the head 64 and around the pipes 65 for in' troducing into and taking cooling medium from this space. The vapor is introduced into a space at the upper end of the condenser 6 and is passed through the tubes 65 into a space at the lower end of the condenser 6. Any portions of the vapor having a higher boiling point than water are condensed in the condenser 6 and may be delivered therefrom by a pipe 68 having a valve 69 which is connected with the lower chamber of the condenser.

A pipe 71 connects the lower chamber of the condenser 6 with the vacuum pump 7 and the vapors are drawn by the vacuum pump 7 from the condenser 6 through this pipe 71. A pipe 73A connects the vacuum pump 7 with an expansion vessel 8 through which pipe 73 the vapors are passed.

The expansion vessel 8 consists of a shell 81A having tight ends 82. Intermediate heads 83 are secured in the shell 8O between which heads pipes 84 extend. A cooling medium is supplied to and taken from a space around the pipes 84 and between the heads 83 by pipes 86. rlhe vapor passes from the pipe 73 into an upper chamber of the expansion .vessel 8 and passes through the pipes 84 into a lower chamber of the expansion vessel 8. During the passage of the vapor through the expansion vessel 8, the condensable constituents thereof are condensed and the permanent gases are taken from the lower chamber by means of a pipe 87, these gases being conducted to tanks or being expelled to the atmosphere. The condensates are taken from 4 the lower chamber of the expansion vessel 8 by means of a pipe 88 having a valve 89. The condensate consists essentially of water and light distillate and is conducted to suitable tanks where the distillate may be separated from the water by gravity, the distillate form ing a valuable by-product.

The clear oil in the still 4 is bleached andI ithe oil has been subjectedto this action for the proper length of time it is taken from thev still 4 by the pressure pump 9 through a pipe 91 which connects to the still 4 through the conical bottom 42 thereof and which has a valve 92. The pump 9 forces the oil which has been mixed with fresh adsorptive material through a pipe 94 to the secondary lter press 10.

The secondary lter press 10 consists of a shell 101 with which the pipe 94 connects. The shell 101 provides a chamber 102 in which a plurality of filter bags 103 are placed. The interiors of these filter bags 103 have pipes 104 connected therewith, which pipes 104 join to a header 106 of the secondary filter press 10 situated on the outside of the shell 101. The clear oil is forced through the bags 103 and passes through the pipes 104 into the header 106, Vthe adsorptive material collecting in a cake on the outside of each of the bags 103, as indicated at 108. The clear oil is separated from the adsorptive material in the lilter press 10 andv is conducted therefrom through a pipe 112, Which connects to the header 106 and has a valve 113, to an oil cooler 11. y

The oil cooler 11 consists of a shell 115 providing a chamber in which a coil 116 is situated. A cooling medium is passed through the coil 116 for cooling the reclaimed lubrieating oil to a normal temperature. The interior of the shell 115 is kept under a vacuum through a vacuum pipe -118 which connects to the pipe 53. The oil is cooled to normal temperature before it comes into contact with the air and is therefore stabilized and will not decompose and odorize. The cooled oil may be drawn from the cooler 11 by a pipe 119 having a valve 120.

The apparatus shown in the drawing comprises no part of my invention and is essentially standard equipment. rlhe primary and secondary filters -3 vand 10 are preferably Sweetland filters which have characteristics this use. I intend to use from 5% to`20% of spent or once u'sed Filtrol in the mixer 1,

such as that which is' taken from the secondary filter 10, and to use from 5% to 15% of fresh Filtrol in the still 4. The percentages4 'of used and fresh Filtrol vary within the above-mentioned amounts, depending upon (1) the condition of the used oil and (2) the desired degree of refinement. This practice is quite. economical and assures a complete adsorption of the impurities.`

As an agglomerating agent I purpose to use vious that my process treats and converts used lubricating oil into a valuable product which may be again used for lubricating purposes.` The reclaimed oil produced by my invention is in some instances better than the oil in its original condition. It is quite obvious that the process of my invention isreally a re-distillation process and therefore the lubricating oil is refined to a greater extent. Any viscosity of oil may be had, this depending upon the time that the clear oil is `treated in the still 4. rlhe longer the oil is treated, the more viscous it becomes.

l claim as my invention:

1. A process for reclaiming used lubricating oil comprlsing: mixing a used lubricating oil with an acid-activated clay material and an agglomerating agent in the form of silicate of soda for adsorbing impurities from said oil; filtering said clay which carries said impurities from said oil; and distilling the light distillates from said oil.

2. A process for reclaiming used lubricating oil comprising; mixing a used lubricating oil with an adsorptive material in the form of an acid-activated clay and an agglomerating agent in the form of silicate of soda for adsorbing impurities from said oil; filtering said adsorptive material which carries said impurities from said oil; and distilling the light distillates from said oil.

3. A process for reclaiming used lubricating oil comprising: mixing a used lubricating oil with an adsorptive material in the form of an acid-activated clay and an agglomerating agent in the form of silicate of soda for adsorbing impurities from said oil; heating said oil during said mixing; filtering said adsorptive material which carries said impurities from said oil; and distilling the light distillates from said oil.

4. A process for'reclaiming used lubricating oil comprising: mixing a used lubricating oil with an adsorptive material in the form of an acid-activated clay and an agglomerating agent in the form of silicate of soda for adsorbingimpurities from said oil; filtering said adsorptive material which carries said impurities from said oil; mixing said oil with afresh batch of acid-activated clay; distilling the light distillates from said mixture; and filtering said second batch of clay from. said oil.

5. A process for reclaiming used lubricating oil comprising: mixing a used lubricating oil with an adsorptive material in the form of an acid-activated clay and an agglomerat ing agent in the form of silicate of soda for adsorbing impurities fronrsaid oil; heating IRG said oil during said mixing; ltering said adsorptive material which carries said impurities from said oil; mixing said oil with a second adsorptive material; distillin the lightdistillates from said mixture; and. terinlg said second adsorptive material from said o1 6. A process for reclaiming used lubricating oil, comprising mixing a used lubricating oil with a previously used acid-activated clay and an agglomerating agent for adsorbing impurities from said oil; filtering said clay from said oil; mixin said oil with fresh acid-l activatcd clay; disti ling the light distillates from said mixture in order to restore the flash, fire and viscositi,T of that portion of the oil left in the still, While said mixture is agitated; and filtering said clay from said residual portion of the oil.

In testimony whereof, l have hereunto set my hand at Los Angeles, California, this 5th day of October, 1926.

` WALTER S. BAYLIS. 

